U.S. patent application number 12/093370 was filed with the patent office on 2011-04-21 for discrete tunable sensing elements and compositions for measuring and reporting status and/or product performance.
Invention is credited to Hans O. Ribi.
Application Number | 20110091391 12/093370 |
Document ID | / |
Family ID | 38541584 |
Filed Date | 2011-04-21 |
United States Patent
Application |
20110091391 |
Kind Code |
A1 |
Ribi; Hans O. |
April 21, 2011 |
DISCRETE TUNABLE SENSING ELEMENTS AND COMPOSITIONS FOR MEASURING
AND REPORTING STATUS AND/OR PRODUCT PERFORMANCE
Abstract
Discrete sensing elements are described that can be integrated
into dental hygiene products and can provide rapid and direct
feedback to a user as to oral environmental status and as to the
performance of the intended oral care product. Selectively tuned
elements can both sense and report relevant information including
usage time, adequacy of performance during use, training for better
usage, and/or the physical or biological status as can be measured
by direct oral contact. Sensing and reporting mechanisms can be
tuned for increased or decreased sensitivities. Sensing elements
can comprise one or more discrete optical changes, structural
changes, or other physical changes to the dental hygiene product as
a means of alerting a user of a stimulus. Use of optical reference
colors provides a high level of accuracy and objectivity as to the
status of a sensing event. Enabling delivery and application
compositions and methods are described.
Inventors: |
Ribi; Hans O.;
(Hillsborough, CA) |
Family ID: |
38541584 |
Appl. No.: |
12/093370 |
Filed: |
November 14, 2006 |
PCT Filed: |
November 14, 2006 |
PCT NO: |
PCT/US06/60871 |
371 Date: |
September 15, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60736967 |
Nov 14, 2005 |
|
|
|
Current U.S.
Class: |
424/48 ; 132/329;
15/167.1; 356/45; 606/161 |
Current CPC
Class: |
A46B 15/0081 20130101;
A46B 15/0002 20130101; A46B 15/0014 20130101; A46B 15/0008
20130101; A46B 2200/1066 20130101; A46B 15/001 20130101 |
Class at
Publication: |
424/48 ; 356/45;
15/167.1; 132/329; 606/161 |
International
Class: |
A61K 9/68 20060101
A61K009/68; G01J 5/60 20060101 G01J005/60; A46B 9/04 20060101
A46B009/04; A61C 15/04 20060101 A61C015/04; A61B 17/24 20060101
A61B017/24 |
Claims
1. An intrinsic visual optical change sensor configured for use
with an oral product.
2. The sensor according to claim 1, wherein said intrinsic visual
optical change sensor undergoes a chromic change in response to a
stimulus.
3. The sensor according to claim 2, wherein said stimulus is a
duration stimulus.
4. The sensor according to claim 3, wherein said duration stimulus
comprises exposure to a temperature in excess of a predetermined
temperature for a predetermined amount of time.
5. The sensor according to claim 2, wherein said chromic change is
a change from a first color to a second color.
6. The sensor according to claim 2, wherein said chromic change is
a change from a hued to a hueless state.
7. The sensor according to claim 1, wherein said oral product is a
toothbrush.
8. The sensor according to claim 1, wherein said oral product is a
dental floss.
9. The sensor according to claim 1, wherein said oral product is a
gum.
10. The sensor according to claim 1, wherein said oral product is a
tongue cleaner.
11. The sensor according to claim 1, wherein said oral product is a
gum stimulator.
12. The sensor according to claim 1, wherein said change is
reversible.
13. The sensor according to claim 1, wherein said change is
irreversible.
14. The sensor according to claim 1, wherein said sensor is adhered
to a portion of an oral care product that is configured for
placement in an oral cavity.
15 to 25. (canceled)
26. A hot melt composition comprising an intrinsic detection
element.
27. The hot melt composition according to claim 26, wherein said
intrinsic detection element provides an intrinsic optical signal in
response to a stimulus.
28 to 51. (canceled)
52. An oral care product comprising a sensor adhered to a portion
of said product that is configured for placement in an oral cavity,
wherein said sensor comprises an applied hot melt composition
comprising an intrinsic detection element.
53 to 62. (canceled)
63. A method for producing an oral care product, said method
comprising: preparing a hot melt composition comprising an
intrinsic detection element; and applying said hot melt composition
to a location on an oral care product.
63 to 109. (canceled)
110. A toothbrush comprising a progression timing sensor.
111. The toothbrush according to claim 110, wherein said
progression timing sensor provides an intrinsic signal in response
to a stimulus.
112 to 148. (canceled)
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Pursuant to 35 U.S.C. .sctn.119 (e), this application claims
priority to the filing date of the U.S. Provisional Patent
Application Ser. No. 60/736,967 filed Nov. 14, 2005; the disclosure
of which is herein incorporated by reference.
BACKGROUND
[0002] Sensing elements find use in a variety of different consumer
and other products and are employed for a variety of different
purposes. Because of their wide-ranging applicability, there is
continued interest in the identification of new sensing elements
for consumer and other types of products.
SUMMARY
[0003] Discrete sensing elements are described that can be
integrated into products including dental hygiene products and can
provide rapid and direct feedback to a user as to oral
environmental or other status and as to the performance of the
intended oral care or other product. Selectively tuned elements can
both sense and report relevant information including usage time,
adequacy of performance during use, training for better usage,
and/or the physical or biological status as can be measured by
direct oral contact or other stimuli. Sensing and reporting
mechanisms can be tuned for increased or decreased sensitivities.
Sensing elements can comprise one or more discrete optical changes,
structural changes, or other physical changes to the dental hygiene
or other product as a means of alerting a user of a stimuli. Use of
optical reference colors provides a high level of accuracy and
objectivity as to the status of a sensing event. Enabling delivery
and application compositions and methods are described.
[0004] Before the present invention is described in greater detail,
it is to be understood that this invention is not limited to
particular embodiments described, as such may, of course, vary. It
is also to be understood that the terminology used herein is for
the purpose of describing particular embodiments only, and is not
intended to be limiting, since the scope of the present invention
will be limited only by the appended claims.
[0005] Where a range of values is provided, it is understood that
each intervening value, to the tenth of the unit of the lower limit
unless the context clearly dictates otherwise, between the upper
and lower limit of that range and any other stated or intervening
value in that stated range, is encompassed within the invention.
The upper and lower limits of these smaller ranges may
independently be included in the smaller ranges and are also
encompassed within the invention, subject to any specifically
excluded limit in the stated range. Where the stated range includes
one or both of the limits, ranges excluding either or both of those
included limits are also included in the invention.
[0006] Unless defined otherwise, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Although
any methods and materials similar or equivalent to those described
herein can also be used in the practice or testing of the present
invention, representative illustrative methods and materials are
now described.
[0007] All publications and patents cited in this specification are
herein incorporated by reference as if each individual publication
or patent were specifically and individually indicated to be
incorporated by reference and are incorporated herein by reference
to disclose and describe the methods and/or materials in connection
with which the publications are cited. The citation of any
publication is for its disclosure prior to the filing date and
should not be construed as an admission that the present invention
is not entitled to antedate such publication by virtue of prior
invention. Further, the dates of publication provided may be
different from the actual publication dates which may need to be
independently confirmed.
[0008] It is noted that, as used herein and in the appended claims,
the singular forms "a", "an", and "the" include plural referents
unless the context clearly dictates otherwise. It is further noted
that the claims may be drafted to exclude any optional element. As
such, this statement is intended to serve as antecedent basis for
use of such exclusive terminology as "solely," "only" and the like
in connection with the recitation of claim elements, or use of a
"negative" limitation.
[0009] As will be apparent to those of skill in the art upon
reading this disclosure, each of the individual embodiments
described and illustrated herein has discrete components and
features which may be readily separated from or combined with the
features of any of the other several embodiments without departing
from the scope or spirit of the present invention. Any recited
method can be carried out in the order of events recited or in any
other order which is logically possible.
DETAILED DESCRIPTION
[0010] The current invention provides for an enabling means to
selectively and specifically locate sensing/reporting elements. The
elements can be positioned in a wide range of locations and
geometries. Combining the multiple features of specific location,
geometry, color selection and contrast, reference colors, and the
like provides both the manufacturer and user of the product an
enabling means to both produce and use the sensing/reporting
mechanisms to the greatest extent and at an exceptionally low and
affordable cost.
[0011] A wide range of different oral products described herein can
benefit from similar location color combination referencing and
geometrical means. In each case, it is important to provide an
accurate sensing mechanism and a clear visual reporting output. The
sensing output can be a one-time event or monitor the progression
of an oral care process. Sensing elements described comprise one or
more discrete optical changes, structural changes, or other
physical changes to the dental hygiene product as a means of
alerting a user of a stimulus. Enabling features of sensing
elements and compositions described include but are not limited to
being discretely located and featured as to provide maximum
sensitivity and selectivity, the ability to be tuned for maximum
performance, and the ability to be specifically designed for
optimal visual clarity, viewing and ease-of-use.
[0012] Sensing and reporting elements described here within may
also find use on a variety of other consumer, household,
commercial, industrial, and technological products and product
categories where a discrete sensing element can be conveniently,
inexpensively, and precisely placed on the product. Conveniently
placing a sensing and reporting element at a strategic location on
a product that can benefit both the producer and consumer while
minimizing the incremental cost can provide a substantial benefit
to both manufactures and consumers alike.
[0013] Categories of oral care/hygiene products can benefit from a
sensing/reporting elements that are appended to or integrated into
the product. By way of example but not limitation various oral
care/hygiene include: toothbrushes including standard toothbrushes,
electric toothbrushes, high frequency sonic toothbrushes, denture
brushes, and various toothbrush alternatives; tooth brushes
incorporating rubber or other cleaning elements or plastic
filaments; denture brushes; toothpicks; bristled between teeth
cleaners; plaque removing dental picks; tooth swabs; finger
toothbrushes; dental floss; hand-held dental floss holders for
adults; dental wax for braces; hand-held dental floss holders for
children; night guards; transparent thermal plastic braces; gum
stimulators including plastic, rubber tipped metal handled
products; wooden stick gum stimulators; dual purpose toothbrush/gum
stimulators; medicinal applicators; dental chewing gum; dental
retainers; metal braces; invisible/transparent plastic braces;
tooth whitening systems, compositions, and devices; dental
implants; dental cleaning instruments and dental picks; water
picks; dental gauss; dental applicators; dental mirrors; dental
power drills including high speed drills; teeth cleaning agents;
self-fitting mouth guard including boil-and-bite mouth guards;
fillings and filling material; implanted posts; dental coatings;
plaque indicators; professional dental tools; tongue cleaners
including tongue scrapers, tongue brushes, and tongue swabs; and
the like.
[0014] Oral care product packaging can benefit from having new
features not previously available to manufactures or consumers. By
way of example, packaging can have "Try Me" features where a
sensing element composition can be placed on a convenient location
on a package containing an oral care product that possesses a
sensing/reporting element. Sensing/reporting element composition
can be positioned and featured on the package such that a consumer
can touch, feel and cause an optical change in the sensing element
without opening the product. Placing a sensing/reporting element on
a package can serve as a particularly important marketing feature
for the oral care product manufacturer to promote the
sensing/reporting element as a new feature on the product.
Alternatively, a sensing/reporting element on an oral care product
package can be used as a temper evidence indicator. If a color has
changed or been distorted intentionally or unintentionally prior to
purchase, the sensing/reporting element can report that product
tampering has occurred. Packaging and product features that promote
the replacement of an oral care product are of particular
importance in order to promote optimal product performance and oral
hygiene.
[0015] By way of more specific examples, sensing/reporting elements
can be specifically employed in selected dental hygiene products to
communicate timing and usage information to the hygiene product
user. The table below summarizes certain oral hygiene products that
benefit from integrated sensing elements by way of example, not
limitation:
TABLE-US-00001 Product Information sensed/reported Visual output
Adult toothbrush 2 minute brushing duration Reversible color
change: color to color and color to colorless - thermal Child's
toothbrush 1-2 minutes brushing duration Reversible color change:
color to color and color to colorless - thermal Toothbrush wear 2-3
months normal usage Irreversible color Indicator change: color to
color - auto polymerization Toothbrush wear 2-3 months normal usage
Irreversible color Indicator change: color to color - shear and
mechanical induced Dental floss 2 minutes flossing time
Irreversible color change: color to color - frictional Dental floss
handles 2 minutes flossing time Irreversible color change: color to
color - frictional on floss. Reversible color to color on handle -
thermal Gum stimulator 2 minutes stimulation Reversible color
(reusable) change: color to change and color to colorless - thermal
Gum stimulator 2 minutes stimulation time Irreversible color
(disposable) change: color to color - frictional Chewing gum Oral
cavity temperature Reversible or irreversible color change above
normal body temperature
[0016] Other consumer, household, industrial, commercial, and
technological products that could benefit from possessing a
sensing/reporting element can include, but are not limited to:
toys, games, art and craft products, safety products, warning
labels, food products, daily use household products, tools,
industrial equipment, health care products, personnel care
products, cosmetic products, bio-technology products, computer
technology related products, printed products, athletic and sports
related products, automotive products, consumable products, product
packaging and novel packaging features where hot melt compositions
are utilized, and the like.
Positioning of Sensor Elements on a Toothbrush or Other Oral Care
Product:
[0017] Sensing and reporting elements can be placed and positioned
on any of a number of locations on a toothbrush or oral care
product. By way of example but not limitation, sensing elements can
be located on regions including: bristles, brush head backside,
brush head side and tip, brush head bristle plane, neck, stem,
handle, bristle holes, attachments to brush, inserts in bristle
area, placed using co-molded materials at various locations,
internally within the body of an oral care product, as an
attachment at a specified location on an oral care product,
insertion of the element to a slot or insertion location on the
oral car product, as a coating, appended as a portion of the
product, as an extension on the product or the like. The sensing
element of material can be a part of a rubberized element on the
brush such as ancillary brushing components contiguous with the
bristles.
[0018] Sensing elements can comprise from a large portion to a
small discrete portion of an oral care device. The sensing element
region can occupy up to the majority of an oral care device to a
small discrete region strategically located on the oral care
device. Selective and discretely placing an element on the oral
care device can markedly enhance the sensing and reporting
capability of the sensing element.
[0019] The sensing element region can occupy from 90% of an oral
care device to a visually acceptably visible percentage as low as
0.05%. Usually, the sensing element region will occupy from 50% to
0.1%. More usually, the sensing element region will occupy from 25%
to 0.5%. Typically and practically, the sensing element region will
occupy from 5% to 1% of the oral care device.
[0020] Discretely placing the sensing element on a selected
location provides for maximum potential interaction, contact, and
accurate reporting. Areas adjacent or nearby to the sensing element
can be selectively colorized to serve as reference colors zones
that either match the initial color of the sensing element prior to
reporting or the final reporting color that the sensing element
converts to after a sensing and reporting event has been
accomplished.
[0021] Oral care products molded with clear resins have the
advantage of good optical clarity. Clear resins can include, but
are not limited to: copolyester (COPET, PCTA, PCTG), polycarbonate,
styrene acrylonitrile (SAN), glycolised polyester terephthalate
(glycolised polyester, PETG), styrene butadiene copolymers (SBC),
cellulose acetate propionate (CAP), polyester terephthalate (PET)
and the like. Such resins can be molded for optimal clarity or be
tinted with various transparent dyes production. More opaque resins
include polypropylene, ABS, high impact polystyrene, polyethylene,
polypropylene, Nylon and the like. Blends of various resins can
also be utilized.
[0022] Good optical clarity provides the advantage of being able to
see a sensing element through the body of an oral care product. An
oral care product can be made with a highly clear and untinted
resin, slightly tinted resins, moderately tinted resins, heavily
tinted resins and translucent resins. For example, a sensing
element on the backside of a toothbrush handle can be seen through
the side of the head or even through the bristle region of the
toothbrush. Seeing the sensing element through the brush allows a
brush user to directly see the sensing element without having to
rotate the brush handle. In addition, the sensing element can be
seen in virtually any position during a brushing session.
[0023] The toothbrush bristle can be further sectioned such that
there is an open region between the bristles. This provides for a
more adequate viewing port between bristles provided that the
sensing element is positioned on the backside of the toothbrush
handle and the toothbrush is molded with a clear plastic resin. The
bristles can be made tufted in two separate sections with a clear
region between each tuft section or a circular patch of tufts can
be eliminated in the center of the bristle area. Various
configurations of bristles can be utilized that optimize the visual
appearance of the sensing element during and between brushing.
Methods for Applying Sensor Elements:
[0024] Various sensor application formats applied to or a part of
oral hygiene product are provided that utilize the compositions
described here within including UV optical coatings, film
laminates, heat/pressure laminates, ink coatings, tab inserts,
injection molded components, pressure sensitive labels, domed
adhesive labels, domed plastic elements, printed components,
solvent based dipping solutions, painting, hot molten dipping
solutions, co-extruding, dip coating, dyeing, sonically welded
components, embossed materials, embedding, hot pressing, co-molded
materials, powder coated materials, vapor deposited layers,
electro-statically adhered material, glued with solvent based
compositions, etched components, and hot melt adhesions, elastic or
inelastic bands for around the brush handle and close to the brush
head, epoxy glues, epoxies comprising sensing materials,
cyano-acrylics, cyano-acrylics comprising sensing agents, UV curing
agents, water based coatings, solvent based coatings labels, tape,
staples that can be firmly embedded in the brush that possesses a
sensing element, magnetic adherence, and the like.
[0025] The sensor material can be applied by painting, dip coating,
ink jet printing, pad printing, lamination, embossing, hot melt
application, liquid injection (hot or cold), liquid application,
tumbling, impregnation, pressing, dye sublimation printing,
chemical treatment, anodization where the oral care product has an
aluminum component to it, laser printing and the like. The coating
or application method will depend on the composition comprising the
sensor material, the desired production process, cost
consideration, ease of implementation, and suitability for the
final product.
[0026] In consideration of selecting an application approach for
sensing/reporting elements, cost-of-goods, ease-of-processing,
versatility, range and ease of formulation, availability of in-line
processing equipment, range of formats, and related features and
attributes should be considered in conjunction with the type of
sensing element of interest and the type of oral hygiene product
for intended integration with.
[0027] Hot melt compositions, hot adhesives, hot glue, and related
thermoplastic adhesive resins are of general interest since they
are particularly amendable to application to an oral hygiene
product during an in-line process. The material and processing
costs associated with hot-melt compositions is low with respect to
other approaches that require pre-fabrication of the sensing
element in a form or format that makes the element satisfactory for
application. Hot melt compositions and application processes
provide for an in-situ approach for forming the sensing element
within a feature or directly onto an oral hygiene device or
product. Furthermore, hot melt compositions can be formulated with
relative ease and utilize temperature and processing conditions
that require less investment in capital equipment compared with
other fabrication approaches.
[0028] By way of example, hot melt adhesion of sensor elements
comprising a thermochromic color change, printed messages on brush
head over-coated with UV/thermochromic window, affixed sensor
tab/labels on the brush head, and printed messages on the brush
over-coated with a UV curable thermochromic window can be utilized.
Hot melt adhesives comprising sensing compositions are of
particular interest due to the ease of locating the composition at
virtually any location on an oral care product. For example, hot
melt adhesives can be applied to various locations on a toothbrush
including: directly to brush bristles, to the brush head, between
bristles that have a separation between the bristles, in bristle
cavities, along side the brush head, on the brush tip, on the brush
neck, along the brush handle, on secondary molded compositions on
the brush and any alternative location on the brush that is
addressable by application of the hot melt composition.
[0029] Hot melt nozzle tips for application of hot melt
compositions can be fine or broadened and provide for accurately
positioning the hot melt extrusion at any position on a brush. Hot
melt compositions can be applied to: the back of the brush head,
the brush tip, the brush side, in or over the bristle holes, on the
handle near the bristles, along the bristles, between bristles,
directly to the bristles in a desired location, and along or on the
handle. The hot melt composition can be applied directly to the
molded surface or to an impression molded into the brush surface.
Applying the hot melt to an impression can provide for a uniform
surface profile without any surface protrusion.
[0030] Impressions for accepting a hot melt formulation can be
pre-molded into an oral hygiene product. The impression can be a
simple circular hole, a disc shaped hole, a groove, a pattern, an
oval, the shape of a symbol, lettering, a square shape, an
insignia, a logo, the shape of a licensed character, or any of a
variety of shapes or renderings that correspond to a design of
interest. The impression can be completely filled with a single hot
melt composition, or multiple compositions to create color change
combinations. The sensitivity of a sensing indicator can be tuned
by adjusting the depth or configuration of an impression that a
sensing material may be applied into.
[0031] The impression can range in depth from being very shallow to
a deep well. The impression depth can range from 0.001 inch to 0.25
deep. Usually, the impression depth will range from 0.005 inch to
0.15 inch deep. More usually, the depth will range from 0.01 to 0.1
inch deep. Most often, the depth will range from 0.025 to 0.1 inch
deep. The depth will depend on the application of interest.
Typically the shallower depths will be used for faster acting and
reporting sensors whereas deeper depths will be used for slower
acting and reporting sensor elements.
Indicating Mechanisms that can be Utilized as a Sensing and
Reporting Means:
[0032] Optical indicating means can include color change mechanisms
and agents, refractive index change materials and mechanisms,
optical sensing mechanisms, capillary fill methods using dyed
fluid, optical obscuring mechanisms and the like. Examples include
but are not limited to: thermochromic, photochromic,
mechanochromic, hydrochromic, chemochromic, biochromic,
bioluminescent, glow-in-the dark materials, encapsulating melting
waxes that melt to reveal an internalized dye, frictionally
sensitive color change materials, dye diffusion, mechanical action
that leads to dye dispersion, pH induced color change materials,
liquid-solid phase transition materials for changing optical
clarity, piezochromic materials, electro-chromic mechanisms, and
the like. The optical indicating means can be selected based upon
the sensing and reporting property of interest. By way of example,
a toothbrush duration indicator can utilize a thermochromic color
change mechanism whereby oral contact at body temperature for a
specified period of time can cause a visual color change in an
indicating element alerting an individual that brushing has been
minimally accomplished for a recommended period of time.
[0033] Alternative outputs that can lead to visual optical changes
include but are not limited to: sheer induced mechanisms, shape
changes in metal alloys or engineered plastics, strain gauges,
piezoelectric induction, reversible stress induced fracturing, and
the like. Micro-optical sensing devices such as those employed for
medical device applications can find use as sensing means on oral
care products (Metrika Inc. CA). Micro-capillary pumping mechanisms
can be employed for use as a sensing and reporting means for oral
care products (Caliper Inc., CA).
[0034] Structural changes signifying timing can be accomplished
using memory alloys. Thermally responsive alloys can be integrated
into an oral hygiene product such that thermal contact during usage
of the product results in a physically observable or otherwise
determinable response. By way of example, a toothbrush can respond
to usage by undergoing a shape change during use. The shape change
occurs in response and correlation to the amount of time used. The
shape change response can be configured in a variety of formats
depending on the desired physical change intended.
[0035] Optical reporting means can take advantage of structural
features of the dental or oral hygiene product. For example, the
bristles of a toothbrush can be made of a fiber optic grade
plastic. Light can be channeled from a light source within the
brush handle directly to the brush bristles. The bristles
themselves can serve both as an illumination source and as a
receptor source for channeling light back to a detector within the
brush. Changes in total internal reflectance of received light can
serve as a real-time means for monitoring various activities,
processes, and conditions during the brushing process.
[0036] Real-time optical feedback can provide a direct means for
product configurations that can both report and respond to oral
hygiene conditions. For example, optical feedback during brushing
can be utilized to signal a response whereby during the brushing
process an agent can be released from an element of the brush that
is intended to assist the brushing process or otherwise provide a
benefit such as increasing the concentration of a tooth whitening
agent. In another example, an optical feedback can be utilized to
activate an ultraviolet light source for activating peroxide-based
materials in a brushing medium to enhance whitening activity.
[0037] Visual displays can be utilized as an output or readout
means including liquid crystal displays, electro-luminescent
displays, electro-chromic displays, light emitting diode displays
and other convenient display mechanisms that provide a clear and
cost effective visual format.
Multiple Sequential and Simultaneous Plural Indicia:
[0038] Multiple sequential or simultaneous sensing and reporting
elements can be incorporated into dental hygiene products. Often it
may be important for more than one sensing means to be present in a
product. For example, a toothbrush could have an indicator that
senses and reports that its use has expired and should be discarded
(e.g. after 3 months use). In addition, the same brush could
possess a second indicator for sensing and reporting brushing
duration (e.g. 2 minutes brushing time). Two or more different
means of sensing and reporting the same process can be utilized on
the same oral care product. By way of example, a light emitting
diode can be incorporated into a toothbrush head and obscured by a
thermochromic agent. The light can be activated by timing
mechanisms. Upon a brushing induced color change in the
thermochromic layer, the light emitting diode can be revealed.
[0039] Multiple sequential color changes can be utilized to
indicate the progression and on-going timing of use of a particular
oral care product. For example, 2 or more thermochromic materials
can be incorporated into a sensing element. The first thermochromic
material can be a red to clear color that changes coloration at
25.degree. C. The second thermochromic material can be a blue to
clear color that change coloration at 29.degree. C. At the
beginning of use, the combined colors will be purple. Upon oral
contact and within 30 seconds or less, the purple color will change
to a blue color due to the elimination of the red color. On further
use of the oral care product and within 60 seconds, the remaining
blue color will turn clear such that no residual color remains.
[0040] Various combinations of color change and optical pigments
can be used in combination to achieve a series of desired effects
during the sensing and reporting process. Thermochromic materials
can be used with glow-in-the-dark pigments. Thermochromic and
glow-in-the-dark pigments can be combined with fluorescent pigments
and the like. Thermochromic materials can be combined with
photo-chromic materials. Photo-chromic materials can be combined
with glow-in-the-dark pigments. A wide range of optical change
permutations can be utilized during the sensing and reporting
process. In an alternative format, structural changes can be
combined with color or optical changes to create a plurality of
outputs that together enhance or reinforce the indication.
Multiple Dye Layers for Specialized Optical Color Changes:
[0041] Specialized dye layers can be utilized to create
unanticipated color change combinations. For example, an underlying
red layer can be over-coated with a thermochromic green to clear
layer. As temperature increases and the green layer turns clear,
the red layer can be exposed. Simply mixing a green pigment with a
red pigment would cause a brown appearance. Keeping the green and
red colors independent provide a visual means of alerting a user
that the beginning and end of use has been accomplished.
Sensing and Reporting Output Status Examples:
[0042] Sensing and reporting elements can be integrated into a
range of different oral hygiene products to assist in monitoring
performance specifications, functions, intended usage, and oral
hygiene status. Sensing elements can be used to report vital
relevant parameters regarding physical, physiological, biological,
chemical, bacteriological, virologic, function. The reporting means
and output can be integrated to match the usage function of the
oral hygiene product. By way of example, but not limitation,
examples of status that can be reported include: brushing duration
time; brushing technique; gum stimulation duration time; gum
stimulation technique; flossing duration and/or technique;
physiologic status including body temperature, hydration, and
dental flora; timing for discarding the oral hygiene product; as an
oral care technique use trainer; as a sterilization indicator; as a
plaque indication sensor; as a salivary enzyme activity sensor; to
indicate the possibility of oral bleeding; to indicate possible gum
disease; physiologic salivary pH status; salivary antibody status;
general health monitoring status based upon salivary constituents
and the like. Concentration means can be incorporated into an oral
hygiene product that can serve as collection means and subsequent
status reporting means.
Single-Use and Reusable Sensing Elements:
[0043] An oral hygiene product can integrate single-use or reusable
sensing elements. Single-use sensing elements can be attached to
the oral care product and provide a one time sensing and reporting
event. The single-use sensing element can be replaced after use
with a new element for use during the next occasion that an
individual intends to use the product. A supply of single-use
sensing elements can be supplied separately from the oral care
product and attached to the product prior to use. After use, the
sensing element can be disposed of.
[0044] Reusable sensing elements will typically be permanently
attached to the oral care product. A reusable sensing element can
be permanently attached to the oral care product by any of a number
of durable means. The reusable sensing element should have the
capability of a reversible sensing and reporting mechanism so that
the element can be regenerated for the next usage.
Structures and Impressions:
[0045] Surface structures, impressions, and emblems can be formed
from an applied hot melt. During setting from the molten phase to
the solid phase, an amorphous hot melt can be molded using a
pre-formed chilling anvil. Immediately after the hot melt is
applied and prior to setting, the chilling surface can be impressed
into the liquefied medium to form a shape of interest. Logos,
insignias, messages, features, and a wide variety of structures can
be formed. The process can be performed off-line so that injection
molding tool changes will not be required.
[0046] High resolution holographic patterns can be impressed,
embossed, debossed, pressed, or patterned into the surface of an
oral hygiene sensor element. The holographic image can present the
opportunity for multiple view points and visual outputs.
Holographic imaging can provide higher resolution patterning and
patterning outputs that appear three-dimensional.
Detachable and Permanently Affixed Sensing Elements:
[0047] The sensing element can be permanently affixed to an oral
care product or be detachable such that a new or different sensing
element can be attached in the same location. This configuration
provides for the possibility that a single oral care product can be
utilized with different sensing probes depending on the desired
function to be monitored. The oral care product can be developed
with an attachment position or port such that a sensing element can
be directly attached to the product. The sensing element can be
developed with a compatible mating mechanism for easy attachment
and de-attachment.
Hot Melt Resin Formulations:
[0048] Ethyl vinyl acetate/vinyl acetate co-polymer, polyethylene,
polypropylene, admixed polyurethane, pure plastic resins with and
without added tackifiers and various combinations have been tested.
A range of commercially available compositions, as well as custom
engineered resins, show feasibility of co-mixing colorants,
acceptable operating temperatures, good adhesion, acceptable
setting times, and good durability.
[0049] Two approaches were pursued for preparation of indicating
hot melt compositions. Commercially available and finished hot melt
products were further processed by melting followed by the addition
of thermochromic colorants or hot melt formulations and colorants
were engineered from selected components. Good colorant acceptance
was achieved in each case. The adherent properties of the
formulated compositions was maintained and tested on polypropylene
as well as co-polyester, polyethylene, and polystyrene toothbrush
samples.
[0050] All compositions and components will need to be certified
for oral contact. Component certification matched with processing
acceptability and product stability are key priorities. Several
vendors and raw materials suppliers have been contacted regarding
regulatory acceptance. Certain tackifying agents, resins such as
EVA's and polyethylene and polypropylene, waxes, polyolefin waxes,
and colorants under consideration should prove to meet acceptable
regulatory requirements. Final formulations, concentrations, and
loading per brush will need to be established.
[0051] A variety of commercial grade hot melt compositions can be
modified with sensing/reporting agents. By way of example, hot melt
compositions utilized of ream wrap for sheeter mills, hot melt
closures, bonding adhesives, freezer grade adhesives, case/carton
adhesives, low memory adhesives, speed case sealer materials,
multi-purpose assembly adhesives, labeling adhesives, product
assembly adhesives, high contact bond adhesives, plastic grade
bonding adhesives, hard to bond surface adhesives, low viscosity
adhesives, long working time hot melts, low density adhesives,
short working time melts, low coloration adhesives, high clarity
adhesives, low clarity adhesives, polyethylene based resins,
polypropylene adhesives, ethyl vinyl acetate adhesives, and the
like.
[0052] Hot melt-based sensing/reporting elements have the advantage
of ease-of-placement, extremely low cost of materials and
application, and versatility of format. Hot melts can be
conveniently applied in small to large dot forms, lines, patterns,
sequences, designs, line-art, logo forms, insignias, lettering or
the like. Hot melt beads can be applied in a continuous or
discontinuous form. Application equipment is readily available and
adaptable to a variety of oral care, consumer, household,
commercial, and industrial products.
Wax Concentration Ranges and Viscosity Modification:
[0053] Hydrocarbon or polyolefin waxes can be added to hot melt
compositions to reduce the composition viscosity at elevated
temperatures. Waxes can range in carbon numbers from 12 carbons to
over 100 carbons per molecule. Usually waxes will range in carbon
number from 15 carbons to 80 carbons. More usually, hydrocarbon
waxes will range in carbon number from 18 to 40 carbons. The
hydrocarbon chain can be straight or branched. The hydrocarbon can
be saturated or contain unsaturated groups such as double or triple
bonds. Various side-chain substituents can be appended on the
hydrocarbon including hydroxyl groups, ether groups, polyether
groups, carboxylic acids, amides, esters and the like.
[0054] Hydrocarbon waxes can be admixed into the hot melt
composition during production. Hydrocarbon waxes can be added at
rations from 0.01% to 90%. Usually waxes will be added from 0.1% to
70%. More usually, waxes will be added to reduce viscosity from 1%
to 50% and typically from 5% to 25%. The amount and type of wax to
be added depends on the desired viscosity at an elevated
temperature, the melt flow index of the formulated hot melt
composition and the adherence characteristics of the final
composition. High wax concentrations tend to reduce the adherence
characteristics of a hot melt composition.
[0055] Hot melt compositions can be formulated such that their
viscosities can be varied form a low level (30-200 centistokes) to
a high level (10.000 to 100,000 centistokes). Final hot melt
compositions can be adjusted in viscosity by resin selection and
the addition of viscosity lower agents such as hydrocarbon waxes.
Viscosities can be adjusted from 30 to 1,000,000 centistokes.
Usually, viscosities will be adjusted from between 50 to 100,000
centistokes. More usually, viscosities will be adjusted from
between 100 to 10,000 centistokes and typically from between 100 to
5,000 centistokes.
Adhesion Enhancements:
[0056] Hot melt application adherence is enhanced using several
different means alone or in combination. Tackifying agents are
typically added to the hot melt composition to improve adherence.
For polypropylene surfaces, the hot melt adhesion can be enhanced
using formulations containing resins more compatible or adherent to
polypropylene (e.g. polypropylene or polyethylene based resins).
Adhesion can be enhanced using corona treatment (hand held unit or
in-line processing). Corona treatment creates chemically more
compatible surface by reducing hydrophobic groups and increasing
hydrophilic groups. Adhesion can be further promoted between a
polypropylene surface and the hot melt by warming or pre-heating
the polypropylene prior to the hot melt application. Surface
roughening, texturing, or indentations can be introduced on the
brush surface to improve entrapment and bonding of the hot melt
composition. Injection molded undercuts can be utilized to
facilitate anchoring of a hot melt composition applied to an
injection molded or machined indent on an oral care product.
Furthermore, increasing the application temperature of a hot melt
composition helps improve the adherence characteristics of the hot
melt composition. Typically application temperatures of between 200
and 500.degree. F. are utilized. More often, application
temperatures between 250 and 450.degree. F. will be utilized. Most
often, application temperature between 300 and 400.degree. F. will
find use as sufficient application temperatures. Higher
temperatures tend to improve adhesion whereas lower temperatures
tend to mitigate adhesion. Combinations of the above can be further
utilized.
Rapid Setting:
[0057] Solid surface chilling can be utilized not only for reducing
setting times, but also as a means to mold or shape the hot melt
composition. By way of example, the chilling means can be used to
flatten a hot melt application bead or dot. Chilling surface can
typically be maintained between room temperature and subzero.
Condensation on the chilling surface may provide an additional
non-stick property for release between the chilled hot melt surface
and the chilling surface. Chilling surfaces can include but are not
limited to: Teflon coated aluminum, Teflon sheet adhered to
aluminum, non-stick silicone rubber sheet adhered to a metal rod,
various metals including aluminum steel, stainless steel, brass,
bronze, copper, oxidized metal surfaces, ceramic coated surfaces,
various powder coated metal surfaces and the like. Contact surfaces
can be polished, patterned, smooth, regular or other wise textured
surfaces. Hot melt compositions can be rapidly impressed, pressed
or flattened with a physical object during cooling or self-leveled
at elevated temperatures and cooled with a stream of cold gas.
[0058] The degree to which the setting time is reduced will depend
on the pressure and temperature that the cold pressed surface is
applied. Rapid setting times can range from 0.1 second (instant
contact) to several seconds (dwell contact). 45.degree. F. Teflon
coated aluminum was used for rapid contact of 0.5 to 1 second. Cold
pressed surface can range from temperatures well below room
temperature yet below the melting transition of the hot melt
composition in the range from -100.degree. F. to 150.degree. F.
More often, cold pressing surfaces will range from -50.degree. F.
to 100.degree. F. Most often, chilling temperature will range from
0.degree. F. to 50.degree. F. Conveniently, chilling may be
accomplished using a solid chilled surface or a stream of chilled
gas.
Tackifying Agents and Concentration Ranges:
[0059] Tackifiers can include rosin based compositions and/or
terpene resin based materials. Tackifiers can be included to
improve the adherence characteristics of a hot melt composition to
typically low adhering substrates such as polypropylene,
polyethylene, and co-polyester. The tackifier can be a pure or
hydrocarbon mixed composition. The composition can be naturally
derived or chemically synthetic. The tackifier is added to a hot
melt composition to selectively or non-selectively improve
adherence of a hot melt composition to a surface of interest.
Tackifiers can be selected and utilized for various properties
including adhesion, compatibility with oral contact, stability, and
compatibility. Tackifiers are commercially available (Arizona
Chemicals, Inc. AZ).
[0060] Tackifying agents can be admixed into the hot melt
composition during production. Tackifiers are added to increase
adhesion between the hot melt composition and the surface that the
composition is intended to be applied to.
[0061] Tackifying agents can be added at rations from 0.01% to 90%.
Usually tackifying agents will be added from 0.1% to 70%. More
usually, tackifying agents will be added to increase adherence from
1% to 50% and typically from 5% to 25%. The amount and type of
tackifying agents to be added depends on the desired adherence
characteristics, compatibility of the tackifying composition and
compatible optical clarity.
Hot Melt Hardening Agents:
[0062] Hardening agents can be added to a hot melt composition to
improve the mechanical stability of an applied sensor element.
Hardening agents include, but are not limited to high temperature
waxes, polyolefin waxes and the like. The addition of waxes can in
addition, decrease and improve the viscosity of the molten state
hot melt composition.
[0063] It is desirable to ensure that an oral cavity sensing
element remain intact and permanently affixed to the oral device
administering the sensing element. Soft hot melt compositions may
be adversely sheared or partially removed by contact with teeth
during use. The addition of hardening waxes can significantly
overcome the weaknesses of non-hardened compositions.
[0064] Hardening agents can be added in the range of 0.1 to over
80%. Usually, the hardening agent will be added at a concentration
of 1% to 50%. More usually, the hardening agent will be added from
5% to 30%. Most often hardening agents will be added in the range
of 10% to 25%. The exact concentration will depend on the desired
hardness and related properties affected by the addition of the
hardening agent.
Hot Melt Production Forms:
[0065] Hot melt indicating formulations can be conveniently cast or
formed into a variety of shapes and configurations useful for
processing, production, and manufacturing. Production and
processing equipment often vary in the type, shape, volume, and
delivery of a hot melt composition and, therefore, it is important
to form or cast an indicating formulation into a relevant and
convenient format. Formats for casting or forming production grade
lots of indicating hot melt formulations can include, but are not
limited to: small pellets (equal to or small than 0.1 inch in
diameter); medium size pellets (0.1 inch to 0.25 inches in
diameter); large pellets (0.25 inch to 1.0 inches in diameter);
small and large discs (0.1 inch to several inches in diameter);
cubes; tiles; rods; ingots; slugs; granulated forms; chopped forms;
sheets; sticks; blocks; dowels; cord; extruded shapes; tubes;
balls; molded shapes; slab forms; various molded pan shapes;
various cast shapes; bullion; shapes meant to fit a particular
heating pot; and the like.
Production Examples:
[0066] In-line hot melt extrusion/applicator can be used to apply a
fully formulated hot melt indicating composition. The hot melt
composition will be supplied in bulk form and added to a heating
tank in the extrusion applicator. The dwell time of the hot melt
composition should be minimized to 1 hour or less at elevated
temperatures (350.degree. F. or above) in order to preserve the
activity of thermochromic agents employed. The bulk hot melt
composition can be added in solid form using an auto-feeder. A
metered amount of liquefied hot melt composition will be supplied
to a heated line and directed to a controlled application nozzle.
The nozzle may be pressure actuated for delivery of a metered
amount. If incremental adhesion is required, an in-line corona
treatment may be required. Corona treatment would be accomplished
prior to hot melt application.
[0067] A recessed circle or compatible hole-shape will be
pre-formed in the brush by injection molding. An insertion pin can
be added to an existing or new mold in the desired dimension and
position. Otherwise, the cavity can be designed and produced with
the ultimate feature of interest. The recessed hole will be used to
accept a metered amount of applied hot melt composition. The recess
volume and hot melt volume will match so that the final sensor
configuration will be level with the brush surface.
[0068] Immediately following application of the hot melt
composition, the hot melt bead will be pressed into a level film so
that the recess hole is completely filled and level.
Pressing/chilling times are anticipated to be one second or less.
The final hot/melt sensor surface can have a smooth or textured
finish depending on specifications. Brushes will be immediately
ready for any final manufacture steps required or for final
packaging.
[0069] Recessed holes or indents may also find use for off-setting
an applied label, decal, tab, tile or the like. The recession can
serve to maintain a level surface on an oral care device. Smooth
surfaces are desirable to ensure comfort during use and to avoid
any oral cavity irritation.
[0070] Sensing elements can be added or applied to a brush or oral
care product at any of a number of introduction points during
production. The sensing element can be added immediately during the
injection molding phase of a toothbrush or product body. The
element can be added directly after molding of the product or brush
body, but before feature of the product are added. In case the
product is a toothbrush, the sensing element can be applied before
or prior to adding bristles to the brush. Good adherence of the
sensing element is required if the element is to be added prior to
bristling. The bristling process often creates aggressive
vibrations and shock. Hot melt applications have the advantage of
strong adhesion and provide the advantage of stable adherence of an
element during and after bristling.
General Configurations and Compositions for Adjusting and
Controlling Response Time of Indicating Sensor:
[0071] The response time for an indicator means can be adjusted to
be an immediate response or a delayed response. The response time
can occur between a millisecond and 24 hours. Usually, the response
time will be adjusted between 0.1 seconds and 1 hour. More usually,
the response time will be between 1 second and 30 minutes.
Typically, the response time will be set for products to be during
the prescribed usage time of an oral care product such as a
toothbrush between 30 seconds and 3 minutes. Dentists often advise
that teeth should be brushed effectively for from one minute to 3
or more minutes. Indicators described herein can be adjusted to
provide an accurate visual sensing and reporting process that
alerts an individual that they have brushed for a recommended
period of time.
[0072] Brushing duration timing can be controlled using one or more
design elements or parameters including: thermochromic color change
temperature transition; thermochromic colorant concentration for
complete color clearing; secondary colorant utilized for signaling
complete color change conversion; thickness of sensor layer;
employing the use of a transparent overlay as a thermal delay;
adjusting the thermal conductivity of the resin; depth of embedding
the sensor element; position of the sensor element on the brush
relative to oral contact during brushing; lighter or darker
reference colors and hues for comparison of end point settings; and
the like.
[0073] Different means can be employed to adjust and tune the
desired response time of an indicator means. The response time can
be adjusted using a thermal delay means such as a transparent
insulating window or insulating layer that covers a sensor or
indicator. The window can create a delay response by insulating a
temperature, chemical, or other physical activation means. The
thicker the window, the longer the delay can be established.
[0074] Insulating layers can be solid, liquid or gaseous. The
resonance time delay between when a sensor surface is exposed to a
change in ambient temperature and when an indicating means is
raised to the ambient temperature depends on the thermal
characteristics of the separating medium between the surface and
the indicating means, time, and thermal contact during usage.
[0075] The thermal properties of a sensing element can be coupled
to or decoupled from an oral care product. A sensing element can be
directly adhered to an oral care product and in direct thermal
contact with the oral care product. In this scenario, the oral care
product can act as a heat sink to the sensing element and
facilitate a delay in the timing of when the sensing element may
respond. Alternatively, a sensing element may be separated from
direct contact with an oral care product by utilizing an insulating
layer between the sensing element and the oral care product. In
this scenario, the oral care product's thermal characteristics
would not impact the thermal characteristics of the sensing
element. In either scenario, the thermal delay characteristics of
the sensing element can be designed to utilize or not utilize the
thermal characteristics of the oral care product that the element
is attached to.
[0076] Timing delay windows can be comprised with clear plastic,
optical ultraviolet cure resin as an over coat, clear pressure
sensitive labels, domed labels made with transparent coatings
(stiff or flexible), color change agent homogeneously mixed in
thickened transparent or semi-transparent layer, laminates,
laminates containing liquid crystal pastes or oils, a cavity filled
with a low thermally conductive gas or a vacuum or the like
[0077] By way of example, a time delay window can range from a 1
micron film to two centimeters. Usually, the window will have a
thickness from 10 microns to 1 centimeter. More usually, the window
will have a thickness from 0.1 millimeters to 5 millimeters. Most
often a window will have a thickness from 0.2 millimeters to 2
millimeters. Typically a practical thickness will be utilized that
will help to create a response within the desired time frame of use
for an oral hygiene product.
[0078] Sensing/reporting elements can be fully embedded and
internalized with in the body of an oral care or other product when
transparent or optically clear resins are utilized for making the
product. By way of example, a sensing element can be embedded,
placed or molded within the interior of a product. The resin
utilized in molding the product can then be gated to completely
encapsulate and seal the sensing element. The molded layer covering
the sensing element can be used to act as a thermal delay window.
The thickness of the thermal delay window produced in the
molding/encapsulation process can range in thicknesses similar to
those described above. Transparent or translucent resins form
encapsulating or molding/sealing a sensing/reporting element can
include, but are not limited to: copolyester (COPET, PCTA, PCTG),
polycarbonate, styrene acrylonitrile (SAN), glycolised polyester
terephthalate (glycolised polyester, PETG), styrene butadiene
copolymers (SBC), cellulose acetate propionate (CAP), polyester
terephthalate (PET) and the like. Such resins can be molded for
optimal clarity or be tinted with various transparent dyes
production.
Alternatively, a thermally responsive chromic change agent can be
evenly or unevenly distributed throughout the layer rather than be
coated by an optically clear window. The concentration of the
chromic change agent can be adjusted along with the total thickness
of the layer such that the optical density of the layer can provide
a sufficient initial and final color contrast change so that a
visual determination can easily be distinguished during a sensing
event.
[0079] The opacity or optical clarity of the sensing/reporting
element composition can be further utilized to affect the visual
timing of the element. Increased opacity in a sensing/reporting
element reduces the visualization of deeper regions within the
sensing element surface. As the color change is initiated, only the
outer layers visually appear to turn color. The lower or more
deeply embedded layers are obscured by the outer layers and
therefore are not seen to change or not change color. Increased
optical clarity in a sensing/reporting element permits light to
more deeply penetrate the sensing layer. The lower or more deeply
embedded layers are more apparent than with opaque sensing
elements. The perceived time delay in sensing/reporting elements
that identical sensing formulations can be increased using more
transparent or optically clear mediums. The perceived time delay in
a sensing/reporting element can be reduced using opacifying
components mixed into the medium. The degree to which it is judged
what time delay should be utilized can be adjusted by changing the
concentration of an added opacifying agent.
[0080] Opacifying agents can include dyes, titanium dioxide,
micro-particulates, talc, microcrystalline materials, optically
dense additives, various fine powders, calcium carbonate,
micro-balloons, nano-particles, non-mixing polymers, opacifing
polymers and the like. Opacifying agents can be added from over 90%
by weight to a sensing/reporting formulations to as low as 0.01%.
More usually, the opacifying agent will be added from 70% to 0.1%.
Typically, the opacifying agent will be added from 50% to 1%. Most
often, the agent will be added from 25% to 5% by weight.
[0081] Higher optical clarity in an optical sensing dye can be
achieved by utilizing smaller grain sizes of the optical agent.
Grain sizes can be produced to the submicron level or below.
Smaller grain sizes of chromic change agents permits more light to
travel through the medium and medium comprising the
sensing/reporting element. Grain sized for the optical change agent
can be from 100 microns or greater to molecular sizes of 10
Angstroms. More often, the dye grain size will be from 50 microns
to 10 nanometers. More usually, the dye particle size will be from
10 microns to 100 nanometers. Most often the grain size for more
transparent compositions will be practically from 500 nanometers to
1 micron in diameter.
[0082] As an alternative thermal insulating layers or windows delay
and timing mechanisms can be accomplished using other means such as
chromatographic migration layers, capillary flow layers, dissolving
mediums, mixing mediums, slow release layers, mechanical sheer and
removal surfaces, chemical change mechanisms, and the like.
[0083] More than physical or chemical characteristics can be used
in combination for fine-tuning the duration response time of a
sensing/reporting element. For example, very short response times
can be achieved using a low temperature thermochromic agent at low
concentrations in a thin layer without a thermal delay window. Very
long response times can be achieved using a high temperature
thermochromic agent at high concentrations in a thick layer and
with a thermal delay window. Permutations of various properties can
be used to achieve a medium time delay. It will be practical to
utilize certain chemical or physical properties for certain
products. The exact combination of sensing/reporting element
properties will depend on the product of interest, manufacturing
process intended, cost-of-goods, features desired and the like.
Film-Based Sensing Indicators than can be Adhered to an Oral
Hygiene Product:
[0084] Sensing and reporting elements can be pre-fabricated
utilizing plastic compositions that comprise both a sensing
reporting optical dye or pigment and a plastic composition that
utilizes any of a variety of standard and engineered resins. The
sensing/reporting optical dye or pigment can be added during the
extrusion process, during film or sheet formation, painted,
printed, or otherwise applied to the plastic composition.
[0085] The film-based sensing/reporting elements can be made with a
wide range of convenient thermal plastics. The element can be
pressure molded, injection molded, thermoformed or vacuum formed,
or the like. Plastics and polymer compositions used for making the
tray include: polyvinyl chloride (PVC), various polyolefins such as
polypropylene and polyethylene, high density polyethylene (HDPE),
low density polyethylene (LDPE), cross-linked high-density
polyethylene (XLPE), softened acrylic, ABS, thick Kapton.TM. tape
materials, Teflon.RTM. (polytetrafluoroethylene (PTFE),
tetrafluoroethylene TFE and fluorinated ethylene polypropylene
FEP)-based materials, brand names such as Kydex, polystyrene,
thermoplastic polyesters, nylon, styrene-butadiene, epoxy casts,
polybutylene, TPX (poly(methyl pentene), terephtalate polyethylene
(PET), PETE, PETF, polyethylene teraphthalate G copolymer (PETG),
polysulfone (PSF), polyurethane (PUR) Thermanox.TM. (TMX),
polymethylmethacrylate, and the like. Strong flexible plastics such
as polycarbonate are often desirable. Polycarbonate can be
thermoformed, pressure formed, and injection molded.
[0086] Other exemplary plastics may include, but are not limited
to: ethylenechlorotrifluoreethylene (ECTFE),
ethylentetrafluorethylene (ETFE), polinvinylidene fluoride (PVDF),
ethylene-propylene rubber (EPR), silicone rubber (SI), Alcryn.RTM.
thermoplastic rubber (TPR), HT thermoplastic rubber (HTPR),
Santoprene.RTM. thermoplastic rubber (TPR), LSOH cross-linked
compounds, LSOH thermoplastic compounds,
methylvinyletherfluoralkoxy (MFA), perflouroalkoxy (PFA),
thermoplastic polyester elastomer (TPE), polyimide (Kapton.RTM.),
polyurethane (PUR), polyvinyl chloride 105.degree. C. (PVC),
polyvinyl chloride 70.degree. C. (PVC), low temperature polyvinyl
chloride (LTPVC), oil resistant Polyvinyl chloride (OR PVC), semi
rigid polyvinyl (SR PVC), polyvinyl chloride polyurethane (PVC
PUR), copolyester (COPET, PCTA, PCTG), polycarbonate, styrene
acrylonitrile (SAN), glycolised polyester terephthalate (glycolised
polyester, PETG), styrene dutadiene copolymers (SBC), cellulose
acetate propionate (CAP), and the like.
Sensing Progression/Timing Features:
[0087] Differential, metered, sequentially timed, and timing
progression can be accomplished by using various thicknesses or
depths of a sensing composition. By way of example, hot melt
compositions, injection molded sensing elements, or otherwise
attached sensing elements can have a depth gradient running along
the length of a sensing element. The thinnest portion of the
sensing element can be formulated to respond immediately to an oral
care process. Progression of the response can be made to continue
along the length of a sensing element such that the thickest
portion will respond last to the oral care process.
[0088] Time sequential indicator designs can include elongated
channels that are filled with a sensing composition where the
channel is shallowest at one end and deepest at the other end.
Circular wells can be made where the depth of the well is
shallowest at the center of the well and deepest at the edges of
the well to be filled with a sensing composition. Circular wells
can alternatively be deepest at the center and shallowest at the
edge. Alternatively, a pedestal or structural feature can be
present at the center of a well geometry such that the feature
remains lower than the top edge of the well, but would still be
submersed beneath the sensing composition intended to fill the
well. The pedestal or feature would provide a rapid indication to a
sensing event where the surrounding deeper portions of the well
would provide a more delayed response. Bulls-eye targets or other
features can be utilized to provide an understandable and
recognizable color change response to an oral care indication.
Spiraled patterns and inclined features can be utilized within a
well such that a timing clock-like feature can be utilized to
display the progression of an oral care indication.
[0089] Sequenced timing events can also be pre-determined using
discrete formulations of sensing compositions. The individual
formulations can be prepared to react to an oral care stimuli at
pre-selected times. The discrete formulations can be applied to an
oral care product adjacent to one another such that each sensing
element comprising the discrete formulation can change color in a
sequential process. By way of example, toothbrush timing indicators
can be formulated for two or more times common to brushing. The
first zone can indicate that 30 seconds have passed. A second zone
can indicate that 60 seconds have passed. A third zone can indicate
that 90 seconds have passed. A fourth zone can indicate the 120
seconds have passed and that brushing is complete. The zones can
comprise the same color change type or different colors to indicate
different timing events.
[0090] Sensing/reporting elements can be made with either abrupt
color change transitions to indicate a "not done" to "done"
transition within a narrow time frame or can be made with a gradual
color change to indicate that a sensing event is in progress and
that the activity should be continued until the color change is
complete. The use of an abrupt or gradual color change will depend
on the product configuration desired. Certain products will find
advantage with an abrupt change so that there is no ambiguity
regarding completion time. Other products will find advantage using
a gradual change so as to keep the user alert and can anticipate
when the process will be complete.
[0091] Key thermal transition variables for controlling brushing
duration can include but are not limited to temperatures of
22.degree. C., 23.degree. C., 24.degree. C., 25.degree. C.,
26.degree. C., 27.degree. C., 28.degree. C., 29.degree. C.,
30.degree. C., 31.degree. C., 32.degree. C., 33.degree. C.,
34.degree. C., 35.degree. C., 36.degree. C.' and 37.degree. C. To
date, the best results for 30 second to 2 minute brushing times
were obtained using 27.degree. C., 31.degree. C. and 35.degree. C.
Shorter delay times of 30-60 seconds can be achieved with
27.degree. C., moderate delay times of 60-120 seconds were achieved
using 31.degree. C. Rapid color change times were seen at
25.degree. C. or lower. Extended or indistinguishable changes were
seen above 35.degree. C.
[0092] Oral cavity temperatures and conductive temperatures to an
oral care device must be considered when employing an appropriate
temperature transition for a sensing/reporting element. Bodily
temperatures, flushing the mouth with a particular water
temperature, the style of usage of an oral care product, the direct
or indirect contact time between the oral cavity and the oral care
product, evaporative cooling of water from the oral care product
during cooling, the degree of agitation of the oral care product
with the mouth during usage and the like should be considered
during design and selection of the physical and chemical
characteristics of the sensing/reporting element to be
produced.
Liquid Crystal Indicators:
[0093] Liquid crystal gel laminate with pearlescence and/or
iridescent color change effects can be utilized as a sensing and
indicting means on oral hygiene products. Liquid crystal strips can
register one or more color change effects indicating a single
duration time or dual or multiple sequential timing durations.
Liquid crystals can be printed on a laminating layer or can be in a
liquefied or gel form and encased or laminated between two layers
to create a thick fluid layer.
[0094] One or more liquid crystal indicating zone may be present.
Multiple indicating zones can be utilized to monitor or observe a
particular oral stimuli. By way of example, three temperature
levels can be placed side-by-side on a toothbrush. The first zone
can be set at a low temperature (e.g. 25 degrees C.), the second
zone at a moderate temperature (e.g. 27 degrees C.) and the third
zone set at a higher temperature (e.g. 29 degrees C.). During use,
the first zone can indicate the initial use of an oral device has
been initiated. The second zone can indicate that use is near
completion, and the third zone can be used to indicate that use has
been successfully completed.
[0095] Protective coatings can be used to cover a liquid crystal
layer. The protective coating can be a polyester film or any of a
variety of clear plastic films. The plastic film can serve both to
protect the liquid crystal layer as well as a thermal delay layer.
Thicker films can be used to further delay a thermal response in
the liquid crystal layer. Thinner layers can be used to keep the
response time to a minimum.
Optical Reporting Dyes and Pigments:
[0096] Thermochromic dyes can find use in a variety of oral care or
oral hygiene applications and formats. Thermochromic dyes can
include but are not limited to compounds including:
bis(2-amino-4-oxo-6-methylpyrimidinium)-tetrachlorocuprate(II);
bis(2-amino-4-chloro-6-methylpyrimidinium)hexachlorod-icuprate(II);
cobalt chloride; 3,5-dinitro salicylic acid; leuco dyes;
spiropyrenes,
bis(2-amino-4-oxo-6-methylpyrimidinium)tetrachlorocuprate(II) and
bis(2-amino-4-chloro-6-methylpyrimidinium)hexachlorodicuprate(II),
benzo- and naphthopyrans (Chromenes), poly(xylylviologen dibromide,
di-beta-naphthospiropyran, Ferrocene-modified
bis(spiropyridopyran), isomers of
1-isopropylidene-2-[1-(2-methyl-5-phenyl-3-thienyl)ethylidene]-succinic
anhydride and the Photoproduct
7,7adihydro-4,7,7,7a-tetramethyl-2-phenylbenzo[b]thiophene-5,6-dicarboxyl-
ic anhydride, and the like.
[0097] Other thermochromic dyes of interest include leucodyes
including color to colorless and color to color formulations,
vinylphenylmethane-leucocynides and derivatives, fluoran dyes and
derivatives, thermochromic pigments, micro and nano-pigments,
molybdenum compounds, doped or undoped vanadium dioxide,
indolinospirochromenes, melting waxes, encapsulated dyes, liquid
crystalline materials, cholesteric liquid crystalline materials,
spiropyrans, polybithiophenes, bipyridine materials,
microencapsulated, mercury chloride dyes, tin complexes,
combination thermochromic/photochromic materials, heat formable
materials which change structure based on temperature, natural
thermochromic materials such as pigments in beans, various
thermochromic inks sold by Securink Corp. (Springfield, Va.),
Matsui Corp., Liquid Crystal Research Crop., or any acceptable
thermochromic materials with the capacity to report a temperature
change or can be photo-stimulated and the like. The chromic change
agent selected will depend on a number of factors including cost,
material loading, color change desired, levels or color hue change,
reversibility or irreversibility, stability, and the like.
[0098] Alternative thermochromic materials can be utilized
including, but not limited to: light-induced metastable state in a
thermochromic copper (II) complex Chem. Commun., 2002, (15),
1578-1579 under goes a color change from red to purple for a
thermochromic complex, [Cu(dieten)2](BF4)2
(dieten=N,N-diethylethylenediamine); encapsulated pigmented
materials from Omega Engineering Inc.;
bis(2-amino-4-oxo-6-methyl-pyrimidinium)-tetrachlorocuprate(II);
bis(2-amino-4-chloro-6-methylpyrimidinium)
hexachlorod-icuprate(II); cobalt chloride; 3,5-dinitro salicylic
acid; leuco dyes; spiropyrenes,
bis(2-amino-4-oxo-6-methylpyrimidinium)-tetrachlorocuprate(II);
bis(2-amino-4-chloro-6-methylpyrimidinium)hexachlorod-icuprate(II);
cobalt chloride; 3,5-dinitro salicylic acid; leuco dyes;
spiropyrenes,
bis(2-amino-4-oxo-6-methylpyrimidinium)tetrachlorocuprate(II) and
bis(2-amino-4-chloro-6-methylpyrimidinium)hexachlorodicuprate(II),
benzo- and naphthopyrans (Chromenes), poly(xylylviologen dibromide,
di-beta-naphthospiropyran, Ferrocene-modified
bis(spiropyridopyran), isomers of
1-isopropylidene-2-[1-(2-methyl-5-phenyl-3-thienyl)ethylidene]-succinic
anhydride and the Photoproduct
7,7adihydro-4,7,7,7a-tetramethyl-2-phenylbenzo[b]thiophene-5,6-dicarboxyl-
ic anhydride, and the like. Encapsulated leuco dyes are of interest
since they can be easily processed in a variety of formats into a
plastic or putty matrix. Liquid crystal materials can be
conveniently applied as paints or inks to surfaces of
color/shape/memory composites.
[0099] Photochromic dyes can find use in a variety of color change
mediums and formats. Photochromic materials can include but are not
limited to dyes including:
1,3-Dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]phenanthr[9,10-b](1,4-
)oxazine]; bicyclo [2.2.1] hepta-2,5- diene; benzyl viologen
dichloride; 4,4'-bipyridyl;
6-bromo-1',3'-dihydro-1',3',3'-trimethyl-8-nitrospiro[2H;
5-chloro-1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-(3H)naphth[2,1-b-
](1,4)oxazine];
6,8-dibromo-1',3'-dihydro-1',3',3'-trimethylspiro[2H;
1,1'-diheptyl-4,4'-bipyridinium dibromide;
1',3'-dihydro-5'-methoxy-1',3',3'; 1',3'-dihydro-8-methoxy-1',3'3'-
trimethyl-6-nitrospiro[2H];
1',3'-dihydro-1'3',3'-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2'-(2H)-in-
dole]; 1,3-dihydro-1,3,3-trimethylspiro[2H -Indole-
2,3'-[3H]naphth[2,1-b][1,4]oxazine];
1,1'-dimethyl-4,4'-bipyridinium dichloride;
5-chloro-1,3-Dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-(3-H)phenanthr[9-
,10-b](1,4)oxazine];
5-methoxy-1,3,3-trimethylspiro[indoline-2,3'-[3H]naphtho[2,1-b]pyran];
2,3,3-trimethyl-1-propyl-3H-indolium iodide and the like.
[0100] Thermochromic color to colorless options can include by way
of example, but not by limitation: yellow to colorless, orange to
color less, red to colorless, pink to colorless, magenta to
colorless, purple to colorless, blue to colorless, turquoise to
colorless, green to colorless, brown to colorless, black to
colorless. Both hued to hueless color state changes and hueless to
hued color state changes can be employed. Color state changes can
include gradual changes from one color to another, rapid color
changes from one color to another, and color state changes that
have a transition history (e.g. the reversal of the color change
can be delayed by formulating the composition to slowly reverse in
color change). Color change histories have the advantage of
prolonged color indication that a oral care process has properly
taken place and can be viewed by other individuals within a
specified time interval.
[0101] Color to color options include but are not limited to:
orange to yellow, orange to pink, orange to very light green,
orange to peach; red to yellow, red to orange, red to pink, red to
light green, red to peach; magenta to yellow, magenta to orange,
magenta to pink, magenta to light green, magenta to light blue;
purple to red, purple to pink, purple to blue; blue to pink; blue
to light green, dark blue to light yellow, dark blue to light
green, dark blue to light blue; turquoise to light green, turquoise
to light blue, turquoise to light yellow, turquoise to light peach,
turquoise to light pink; green to yellow, dark green to orange,
dark green to light green, dark green to light pink; brown and
black to a variety of assorted colors, and the like. Colors can be
deeply enriched using fluorescent and glow-in-the-dark or
photo-luminescent pigments as well as related color additives.
[0102] Photo-luminescent compounds can find use in a variety of
color change mediums and formats. Photo-luminescent compounds can
include, but are not limited to, a variety of materials. Greens,
green blue and violet can be made with alkaline earth aluminates
activated by rare earth ions. By way of example, strontium
aluminate can be activated using europium (SrAl03:Eu). Visual
wavelengths can include: green at 520 nm, blue-green at 505 nm, and
blue at 490 nm. Red and orange colors can be generated with zinc
sulfide.
[0103] Fluorescent dyes can find use as additive colorants or
background colorants to various color to colorless thermochromic
dyes. Fluorescent dye compounds can include but are not limited to:
fluorescein, fluoresceine, resourcinolphthalein, rhodamine,
imidazolium cations, pyridoimidazolium cations, dinitrophenyl,
tetramethylrhodamine and the like. A wide range of fluorescent dyes
that can be activated at various wavelengths and emit light at
lower wavelengths can be purchase from Sigma-Aldrich (Saint Louis
Mo.) or Molecular Probes (Eugene Oreg.). Fluorescent dye pigments
are commercially available form various vendors (e.g. Day-Glo
Corporation, Cleveland, Ohio)
[0104] Other optical pigments can be added to the thermal
impression setting composition to create a variety of practical
optical effects. By way of example, glow-in-the dark pigments may
be added in order to help an individual locate the oral care
product in a dark room. Photo-luminescent compounds can find use in
a variety of color change oral care product mediums and formats.
Photo-luminescent compounds can include but are not limited to a
variety of materials.
[0105] Greens, green blue and violet can be made with alkaline
earth aluminates activated by rare earth ions. By way of example,
strontium aluminate can be activated using europium (SrAl03:Eu).
Visual wavelengths can include: green at 520 nm, blue-green at 505
nm, and blue at 490 nm. Green, red and orange colors can be
generated with are zinc sulfide. Color change and/or luminescent
materials can include but are not limited to photo-luminescent
material such as glow-in-the dark complexes such as copper doped
zinc sulfide (Hanovia Corporation).
[0106] Of particular interest are classes of polymeric
thermochromic dyes such as polydiacetylenic compounds,
polythiophenes, and other polymeric materials that possess
thermochromic color change characterizes. Polymer based
thermochromic materials like polydiacetylenes have certain
advantages including their large molecular weight and adjustable
physical characteristics. Polydiacetylenes also possess the optical
thermochromic property of undergoing a continuous hue change during
a thermochromic transition. Initially at low temperatures, they can
exist in a deep blue state. As the temperature is increased they
begin to change their conjugation length and blue hues become mixed
with red hues to appear deep purple. As the temperature continues
to increase toward the transition temperature, the red hue dominate
and magenta colors begin to appear. At temperature close to the
transition temperature, red hue over come any residual blue tones
and the color becomes deep red. At the transition temperature, the
polymer exhibits primarily a red hue. As the temperature rises
above the transition, the color becomes orange. At even higher
temperatures above the transition temperature, the color becomes
bright yellow orange.
[0107] Optical reporting pigments of dyes can serve as indication
means to help alert an individual of proper handling condition
during use. Thermochromic dyes or pigments can be used as an
indicating means to visually determine when the impression
compositing has achieved the correct softening level during initial
heating. The thermochromic change can indicate the ideal impression
formation temperature. The thermochromic color change can find use
to indicate an adequate temperature for re-molding the impression
material for devices intended to be reused and refitted. A
thermochromic dye or pigment can importantly indicate a critically
high temperature that could cause scalding and oral burns during
initial fitting. A thermochromic change can provide a benefit by
indicating when a device has been adequately sterilized prior to
initial or subsequent use. A thermochromic dye or pigment can be
used to indicate when an ideal temperature has been achieved to
release an active component for time impression material matrix
such as a whitening agent or medicinal compound. The thermochromic
change can be a single distinct visual change. More than one
thermochromic change can be used to indicate more than one
temperature criteria. The thermochromic change can be distinct from
one color to another, from a colorless state to a colored state,
from a colored state to a colorless state, undergo a continuous hue
change throughout a complete thermal cycling of an impression
device, or the like.
[0108] The thermochromic change can be irreversible or reversible.
An irreversible thermochromic change can be used as a single event
to indicate that a single temperature objective has been met. By
way of example, it may be desirable that the color changes from one
color to another to indicate that the device is specifically ready
for insertion after heating has been accomplished or that the
device has been sterilized a single time and is safe to use.
[0109] Reversible color changes can find a wide variety of uses in
that that the color change can be recycled and repeated during
repeat uses of the device can successfully report multiple
sequential temperature setting before, during and after the
impression setting process. More often reversible color changes can
be utilized repeatedly for multiple indication means and provided
continual value since if device is intended for re-fitting, then
the thermochromic change should be reversible.
[0110] A dye system can be used as a wear-use indication means that
reports that the device has been adequately used and should be
discard and replaced with another new device of the same type. The
substrate material and indicating dye can be adjusted jointly to
ensure that when continued use begins to exhibit a discrete color
change or the like signaling that device should be disposed of and
not to be continued to use.
Thermochromic Colorant Concentration:
[0111] Thermochromic agents can be utilized as an indicating means
by adding the agent in an appropriate form depending on the
composition of the indicating formulation. A thermochromic agent
can be added from concentrations as low as 0.01% to over 90%.
Usually a thermochromic agent will be added at concentrations
ranging from 0.1% to 70%. More usually, thermochromic agents will
be added from between 1% and 25% and typically from between 2% and
15%. The concentration of thermochromic agent utilized will depend
on the specific application of interest, the desired color contrast
to be achieved, the richness of coloration achieved, the time delay
of interest desired, and consideration of material cost and
practicality.
Active and Inactive Dye/Colorant Additive Concentrations:
[0112] Various inactive and active dyes can be added at
concentrations of interest to achieve an optical effect of
interest. The dye can be inactive such as an FD&C dye or active
such as a glow-in-the-dark pigment or fluorescent dye. Dyes can be
added from concentrations as low as 0.001% to over 90%. Usually a
dye will be added at concentrations ranging from 0.01% to 50%. More
usually, thermochromic agents will be added from between 0.1% and
25% and more often from between 0.5% and 15%. Most often
concentrations between 1% and 5% will find use in most
applications. The concentration of dye utilized will depend on the
specific application of interest, the desired color contrast to be
achieved, the richness of coloration achieved, and consideration of
material cost and practicality.
Contrast Matching with Reference Colors on Brush:
[0113] Various regions, sections or elements of an oral care
product can be comprised with an inactive color zone or have a
feature on the product that possess a particular coloration. The
inactive or stationary color can be used as a reference color to
match either an initial color or a secondary (changed color) and
serve as a reference color for comparison. By way of example, the
handle of a toothbrush may have one of its compositions or features
colorized with a particular hue as a reference color. Likewise, the
initial color of a sensing element may be colorized with a color
change composition that matches the composition of feature on the
toothbrush handle. During a sensing and reporting event, the
initial color of the sensing element will change such that the
color match between the reference color and the sensing element
will be contrasted.
[0114] Similarly, the reference color may be colorized to match a
secondary color that the sensing element may change to. By way of
example, a toothbrush may have a feature that has a particular hue
or color that is initially different than the starting color of a
sensing element. During a sensing and reporting event, the color of
the sensing element will change from a contrasting color with
respect to the reference color to a color that matches the
reference color.
[0115] Unlike descriptions in U.S. Pat. No. 4,957,949, it is
important that a discrete and readable sensing element be
positioned such that a clear and unambiguous reporting response can
be achieved. U.S. Pat. No. 4,957,949 describes a method by which
that the entire toothbrush changes color either on the handle or
the toothbrush head. Describe sensing/reporting elements can be
placed in specific locations such as the back of a toothbrush head.
Importantly, adjacent to the sensing element can be a reference
color zone that indicates and matches a color that the reporting
sensing element either starts with or ends with. Alternatively,
discrete sensing element when used can changed from a particular
color utilized in the toothbrush itself to another color. For
example, the sensing reporting element can be placed in a small
diameter circular pattern on the back of the toothbrush head. The
sensing/reporting element can have an initial color that is
significantly different in contrast from the toothbrush body. As
brushing occurs and the brushing duration limit has been achieved,
the sensing/reporting element can become the same color as the
toothbrush body and therefore indicate precisely that the adequate
brushing duration has been achieved.
[0116] Assuming the toothbrush body is a non-colored white
composite, the sensing/reporting element can be any of a wide range
of initial starting colors. Colors can include but are not limited:
red, blue, green, yellow, magenta, pink, purple, turquoise, orange,
brown, black, and a wide range of related hues and colorations.
Alternatively, the toothbrush body or portions of the toothbrush
body can be pre-colorized to match either the initial
sensing/reporting element color or the final sensing/reporting
element color. These configurations provide a significant color
change contrast and eliminate the ambiguity associated with the
entire toothbrush changing color without any reference colors
present.
[0117] The following examples are offered by way of illustration
and not by way of limitation.
EXPERIMENTAL
Example 1
[0118] Brushing duration sensor using optical coating formulation:
An optical coating formulation possessing a thermochromic sensing
liquid formulation was prepared. An ultraviolet light sensitive
resin was used as base coating composition (Nazdar 3227 UV mixing
clear, Nazdar Corporation). 4% by weight dry powder thermochromic
colorant (Keystone Corporation, Il, blue 29 degrees centigrade
temperature transition) was added to the UV resin and mixed
thoroughly to a uniform state (room temperature). Coating
compositions were prepared in advance of use and stored at room
temperature. Additional compositions were prepared with higher and
lower temperature thermochromic agents including 25, 27, 31, 35 and
37 degrees centigrade).
Example 2
[0119] UV/thermochromic optical indicating brushing duration
sensor: The back surface of a polypropylene tooth brush head was
surface roughened using a 300 grit sand paper. The surface was
roughened to ensure good adhesion between the UV/thermochromic
coating and the polypropylene surface. Alternatively, surfaces can
be treated using a corona discharge to enhance the hydrophilic
property of the surface. The UV/thermochromic liquid formulation
was applied directly to the treated brush head surface. 20 micro
liters were applied and allowed to spread out directly into a
circular pattern.
[0120] The wetting angle of the fluid was such that the edges of
the applied region thinned to 0.05 inches. The UV/thermochromic
solution was rapidly cured using a UV lamp system (1200 watts per
square inch, medium pressure lamp). The applied solution was
initially quickly exposed to the UV lamp at a distance of 10 inches
for 2 seconds. The curing process was prolonged to ensure minimal
over heating and reduced potential to photo-bleach the color
components. The applied solution was subsequently exposed more
intensely at a distance of 6 inches from the lamp source for 4
seconds. The coating became firmly cured by touch to a hardened
solid state.
Example 3
[0121] Printed message brushing duration sensor using over-coated
with UV/thermochromic window: A message was screen printed on the
back-side of a toothbrush head using a stationary UV ink. The
printed message was rapidly cure printed message using intense UV
light source. The message was over-coated using a UV/thermochromic
liquid formulation (above). The over-coat UV/thermochromic liquid
was rapidly cured using the same light source as was used for
curing the stationary UV ink.
[0122] Messages can be either printed using a silk screen method or
an alternative method such as pad printing. The ink was applied in
a thickness sufficient to clearly delineate the message of interest
and provide for suitable adhesion characteristics to the toothbrush
surface. For UV treatment and curing of UV stationary inks, a
medium pressure mercury vapor UV lamp system (1200 watts/inch
squared) was employed. Printed samples were exposed at full
intensity for 3 seconds at a distance of 6 inches from the bulb.
Care was taken not to over expose the ink formulation or over heat
any component of the toothbrush. Message printed toothbrush samples
could be further processed immediately or stored for further
processing late a later stage.
[0123] A UV/thermochromic optical coating was placed over the
message by applying the coating from a low pressure liquid
applicator. A metered amount of UV/thermochromic solution was
applied such that the coating self-leveled on the brush surface
resulting in a thickness of 0.05 inch at the central height. The
wetting angle of the fluid was such that the edges of the applied
region thinned to 0.05 inches. The UV/thermochromic solution was
rapidly cured using the same UV lamp system described above. The
applied solution was initially quickly exposed to the UV lamp at a
distance of 10 inches for 2 seconds. The curing process was
prolonged to ensure minimal over heating and reduced potential to
photo-bleach the color components. The applied solution was
subsequently exposed more intensely at a distance of 6 inches from
the lamp source for 4 seconds. The coating became firmly cured by
touch to a hardened solid state.
[0124] The advantages of using optical UV coatings containing the
thermochromic agent to obscure a message includes the ease of
changing the message from time to time as desired and the use of
low cost materials that involve only a limited amount for
production of a workable toothbrush product. Materials and
components can be specified and formulated to be in compliance with
the Food and Drug Administration's criteria for use in oral contact
applications.
Example 4
[0125] Simplified hot melt formulation for duration sensor
applications: A simplified hot melt composition was formulated in
order to comprise a brush timing duration indicator. A low melt
temperature polyethylene resin (melt index of 4000 at 300 degrees
F.) was utilized as the base material. 300 gram resin was heated to
350 degrees F. in a convention oven. 8% by weight master-batched
thermochromic colorant (Matsui International, Inc., Gardena Calif.
Type 27 degrees C. color to colorless pigment, polyethylene master
batch) was added to the molten resin and mixed thoroughly. 0.1% to
1.0% by weight of a compatible fluorescent dye pigment was added to
create a bright color to color change (Dayglo Company). The
fluorescent dye pigment was mixed uniformly into the molten
resin.
[0126] After the indicating hot melt composition was completely
blended, hot melt sticks were cast by pouring the mixture into
rod-shaped silicon rubber molds. The molds formed 3/8 inch in
diameter rounded rod shapes 6 inches in length. The cast rods were
immediately ready for use once they had been cooled to room
temperature and removed from the mold.
Example 5
[0127] Strengthened adhesive hot melt formulation for duration
sensor applications: The simplified hot melt composition described
above was modified with a tackifying agent. A low melt temperature
polyethylene resin (melt index of 4000 at 300 degrees F.) was
utilized as the base material. 300 gram resin was heated to 350
degrees F. in a convention oven. 8% by weight master-batched
thermochromic colorant (Matsui International, Inc., Gardena Calif.
Type 27 degrees C. color to colorless pigment, polyethylene master
batch) was added to the molten resin and mixed thoroughly. 0.1% to
1.0% by weight of a compatible fluorescent dye pigment was added to
create a bright color to color change (Dayglo Company). The
fluorescent dye pigment was mixed uniformly into the molten resin.
15% by weight tackifying agent (Arizona Chemical Comp. AZ) was
added to the simplified formulation. The tackifying agent was
blended to uniformity with the other composition components.
[0128] After the indicating hot melt composition was completely
blended, hot melt sticks were cast by pouring the mixture into
rod-shaped silicon rubber molds. The molds formed 3/8 inch in
diameter rounded rod shapes 6 inches in length. The cast rods were
immediately ready for use once they had been cooled to room
temperature and removed from the mold.
Example 6
[0129] Hardening hot melt formulations: Hot melt formulations can
be hardened for improved integrity during use. In particular, it is
important to minimize scratches and abrasions to the sensor surface
during usage. Hardening polyolefin waxes can be added to improve
the overall strength of a formulated sensor element. Hot melt
formulations made similar to Example 5 above "Strengthened adhesive
hot melt formulation for duration sensor applications". Were
strengthened using 15% hardened polyolefin wax. The wax was added
during the heated stage and all compositions were completely melted
and mixed thoroughly.
Example 7
[0130] Bulk production preparation of sensing/reporting hot melt
compositions: Hot melt compositions were formulated similar to
described above. Bulk preparations were prepared with 8% by weight,
master-batched thermochromic pigments (Matsui International,
Gardena, Calif.). Resins were prepared with pre-formulated hot melt
compositions (industrial adhesives ink, OR) or pure polyethylene
resins (polyethylene polymer, 4000 centipoises at 350 degrees F.).
Bulk formulations were prepared by initially pre-melting the hot
melt resin 350 degrees F. for 1 hour or until liquefied. The hot
melt composition was maintained in a clear liquid state prior to
adding the master batched thermochromic pigment (polyethylene resin
based). The thermochromic master-batched pigment was added in
pellet form over the surface of the molten hot-melt resin. The
entire composition was maintained at 350 degrees F. for 15 minutes
or until the pigment was completely molten. Once the pigment was
completely molten, the composition was stirred until the
formulation was completely mixed. Complete mixing was achieved once
all of the master-batched pigment resin was homogeneously
dispersed.
[0131] Pre-sized and weighed ingots were prepared from the molten
composition. Typically 1 lb ingots were prepared by pouring the
molten composition into cylindrical nonstick tubing approximately 3
inches in diameter and 1 foot in length. The molten composition was
easily weighed by placing the nonstick tubing vertically on a
nonstick platform and sealing the two components together. The hot
melt formulation was directly poured into the open top of the
cylinder until the desired weight was achieved. Cylindrical
canisters were cooled to room temperature by submersion in a water
bath. For use, the ingots were removed from the cylinders by
lightly tapping them and sliding them out. The preformed ingots
could be used directly in standard hot melt automation equipment
(e.g. ITW Dynatec Corporation)
Example 8
[0132] Hot melt duration sensor in circular indent format: A
polypropylene toothbrush head was prepared by machine milling a
0.25 inch in diameter hole 0.05 inch deep. The impression was
milled in the brush head to contain and be filled by the hot melt
formulation. The hot melt indicating materials cast into rods were
melted in a low temperature hot melt gun. The indicating hot melt
formulation was extruded into the machined indent.
[0133] Approximately 50 milligrams hot melt indicating formulation
was applied to fill the indent. The indent was filled to completion
with the surface level and flush with the upper level of the
toothbrush surface. The molten hot melt indicating formulation was
flattened using a flattened anvil coated with a silicone rubber
coating. The coating prevented any sticking. The flattened anvil
surface helped to level the hot melt formulation and accelerate
cooling to a solidified state. The indicating brush was ready for
use immediately after cooling the sensor to room temperature.
Example 9
[0134] Automated duration sensor production process: An automated
process for sensor/reporting toothbrush duration sensors was
developed. Injection molded toothbrushes with a circular indented
recess as described above were used in combination with production
processed thermochromic sensing/reporting compositions also
described above. The sensing/reporting compositions were utilized
in automated hot melt production processing equipment (ITW Dynatec
Corp.) The system was set up as follows: The hot melt reservoir was
maintained at 350 degrees F. for melting the hot melt composition.
The reservoir was filled with between 5-10 lbs of the hot melt
formulation. A heater connector hose was maintained at 350 degrees
F. and under low pneumatic pressure. High precision applicator
nozzle was maintained at 350 degrees F. The applicator nozzle on an
X, Y, Z positioning stage. Each system component was controlled
using PLC controllers and algorithms. Pressures, nozzle sizes and
process parameters were controlled such that the exact volume
equivalent of hot melt composition could be delivered to the
indented recess on a toothbrush. Sequential toothbrush fixtures and
holders were adapted to a step and repeat linear transition stage
(also computer controlled). The step and repeat functions as well
as a hot well melt applicator functions were programmed such that
an accurate volume of hot melt composition could be applied to a
toothbrush every 2.5 seconds. The system design is capable of
applying the hot melt composition to two toothbrushes
simultaneously. The total system throughput was capable of applying
continuous production runs with high throughput.
Example 10
[0135] Hot melt duration sensor in patterned format: A hot melt
duration sensor format was produced as described above. The indent
was machined as a word pattern "DONE". The wording was engraved in
the toothbrush head using a high-speed engraver. The hot melt
sensing formulation was prepared according to Example 5 above
"Strengthened adhesive hot melt formulation for duration sensor
application". The color of the cold sensing formulation was matched
with the color of the polypropylene brush handle. During use, the
word "done" appeared during brushing due to the color change as
brushing progressed.
Example 11
[0136] Indicating color change dental chewing gum: A thermochromic
temperature indicating chewing gum was prepared to monitor oral
cavity temperatures. The chewing gum was capable of indicating
normal body temperatures and/or fever elevated body temperatures
greater than 99 degrees F. Chewing gum base was blended with a
sugar substitute (0.5% by weight), corn starch (10% by weight), and
a thermochromic pigment (2% by weight, temperature transition set
at 99 degrees F., blue to clear leuco dye) and a colorfast red food
dye (Red 28, FDC lake pigment). The composition was blended under
molten conditions at 250 degrees F. for 20 minutes and then
processed into 0.5 inch wide 1.0 inch long and 0.2 inch thick
tiles.
[0137] The formulated gum was a deep purple color at room
temperature. Upon chewing and below 99 degrees F., the gum remained
light purple. When oral temperatures at or above 99 degrees F. were
monitored, chewing resulted in the gum transitioning from a purple
color to a red color. The chewing gum remained red so long as
chewing continued and until the gum was expelled. The chewing gum
could accurately be used to monitor fever level temperatures at or
above 99 degrees F.
Example 12
[0138] Toothbrush life-time sensor using hot melt formulation: A
medium temperature hot melt formulation can be utilized as an
irreversible color change indicator for determining the useful
life-time of a used toothbrush. The sensor formulation can comprise
a colorless to color change or a color to color change such that
utilization of a formulated sensor causes an irreversible color
change over a prolonged and specified period of time reflecting the
useful life-time of the toothbrush. The mechanical shear and
contact effect of brushing during which teeth and gums come in
contact with the sensor results in a structural impact on the
surface of the sensor. The structural impact result in structural
shear force change in the sensor composition that disrupts
encapsulated leuco-dyes resulting in a distinct color change. The
degree of structural shear force over time can be directly related
to the total usage of the toothbrush. The composition can be
formulated accordingly to accommodate a manufacturer's suggested
usage duration.
Example 13
[0139] Pressure sensitive brushing duration polyethylene films for
pressure sensitive adhesive attachment: Polyethylene resin (General
Polymers, division of Ashland Chemicals: PE HUN2051 NT) was
co-extruded with 7% by weight master batch polyethylene
thermochromic colorant (Matsui Corporation, CA: type 27.degree. C.
color to colorless or color to color). Colors utilized to make
sheets included green to colorless, magenta to colorless, blue to
colorless, orange to colorless, yellow to colorless, green to
yellow, purple to red, purple to blue, green to orange and orange
to yellow. Extrusion was performed with a 1 inch extruder using a
mixing screw and 3 heated zones (Wayne Machines, Inc.: zone 1 at
390.degree. F., zone 2 at 350.degree. F., and zone 3 at 325.degree.
F.). Extruded rods were formed and then stored for later use.
[0140] Films were compression molded using a 125 ton heated platen
hydraulic press (Wabash Corporation: 6 opening 28 inch by 28 inch
platen size). Initially, the extruded plastic rods (1/2 inch in
diameter, 8 inch in length) were preheated and softened at
275.degree. F. for 10 minutes. The 400 gram preheated rods were
placed between preheated Teflon coated aluminum sheets (1/8 inch
thick, 28 inch by 28 inch square, preheated to 300.degree. F.). The
sheet/rod sandwich was placed in the pre-heated platen press
(preheated to 300.degree. F.). The rods were pressed to a sheet
thickness of 0.05 inch.
[0141] Pressure sensitive adhesive in a double stick format (3M
Corporation, 0.005 inch thick, general purpose) was applied to one
side of a pre-formed polyethylene sheet. Tabs were die cut from the
pressure sensitive sheet stock using a steel rule die (0.25 inch
wide, 0.5 inch long with a 0.125 inch rounded radius at each end).
The die cut pressure sensitive sensor tabs could be directly
adhered to the back side of toothbrush heads. The pressure
sensitive adhesive was firmly seated using moderate pressures for
application.
Example 14
[0142] Pressure sensitive film applied as a brushing duration
sensor: The die cut sensor tab/label prepared as described above,
was affixed on nested brush directly on the back-side of the
toothbrush head. The tab was firmly adhered using a pressure
sensitive adhesive laminated on the sensor tab/label. The
toothbrush was immediately ready for use. In similar cases the
sensor tab could be adhered using hot melt adhesives, heat
laminated using a high-pressure heat laminator, or sonically welded
using a sonic welding apparatus.
Example 15
[0143] Brushing duration sensor showing time progression: The
duration indicator was prepared with a depth gradient well from
0.005 inch to 0.050 inch. The well was machined into a
polypropylene toothbrush handle. The total well length was 2
centimeters and was machined on the back side of the toothbrush
head. The sensing composition was prepared according to Example 5
above "Strengthened adhesive hot melt formulation for duration
sensor applications". The thinner region changes color first during
brushing to indicate that brushing is partially complete. As the
brushing time comes to completion, the thicker portion of the
indicator turns color. A complete color change along the length of
the indicator indicated that brushing has been accomplished for the
expected duration. The progression of brushing timing was easy to
follow as the color changed along the axis of the gradient
well.
Example 16
[0144] Toothbrush use and expiration sensor: A toothbrush use and
expiration sensor was generated using a hot melt composition
including an encapsulated leuco dye. The leuco dye was combined
with a medium temperature polyethylene resin and a hot melt
adhesive composition. The leuco dye was added at 3% by weight
powder (Color Change Corporation). The leuco dye utilized had a
stated temperature transition of 22.degree. C. The polypropylene
resin was added at 30% by weight (medium density polypropylene from
Ashland Chemicals).
Example 17
[0145] Toothbrush duration indicator with embossed reflective and
holographic patterns: The hot melt surface can be embossed,
textured, or finished with a holographic pattern. The embossing or
patterning process can occur immediately upon pressing a deposited
molten hot melt sensing material. The cooling and flattening
surface intended for pressing the molten composition can be
patterned with the reverse image intended to be impressed into the
surface.
[0146] Other oral care product examples include, but are not
limited to: a brushing duration sensor that uses a liquid crystal
gel label format; dental floss use-based color change as an
indicator composition for proper usage and timing; plural
indicators for brushing duration and for brush life-time; a gum
stimulator duration sensor for indicating appropriate usage timing;
a toothbrush duration indicator with a green/go color change to a
red/stop brushing sensor timer; fluorescent/thermochromic colorants
for brushing duration sensor applications; metallic
flake/thermochromic colorants for brushing duration sensor
applications and related examples.
[0147] Additional product examples may include, but are not limited
to: warning indicating dots on consumer products; tamper evident
indicators indicating that a product has been violated prior to
purchase or intended use; automotive products where use or over-use
should be indicated; household cleaning products where it is
important to indicate levels, strength, temperature-of-use or the
like; food products where it is important to indicate expiration,
freshness; intended storage temperatures, tamper or the like;
medicinal products where it is important to indicate sequence of
use, storage temperature, storage conditions or the like, toys
where it is important to indicate intended play patterns, proper
usage, replacement time of a feature, safety features, new toy
embodiments or features; usage and "Try Me" features on cosmetic
products; novel packaging elements where, for example, hot melt
compositions can be used not only for glue, but for interactive
purposes such as "Try Me" features, interactive features,
attractive color change features, and the like; and household
mending and gluing products such hot melt guns, glue guns and hot
melt resins where it is important that the applied resin can have a
new color change component and sensing/reporting
characteristics.
[0148] Although the foregoing invention has been described in some
detail by way of illustration and example for purposes of clarity
of understanding, it is readily apparent to those of ordinary skill
in the art in light of the teachings of this invention that certain
changes and modifications may be made thereto without departing
from the spirit or scope of the appended claims.
[0149] Accordingly, the preceding merely illustrates the principles
of the invention. It will be appreciated that those skilled in the
art will be able to devise various arrangements which, although not
explicitly described or shown herein, embody the principles of the
invention and are included within its spirit and scope.
Furthermore, all examples and conditional language recited herein
are principally intended to aid the reader in understanding the
principles of the invention and the concepts contributed by the
inventors to furthering the art, and are to be construed as being
without limitation to such specifically recited examples and
conditions. Moreover, all statements herein reciting principles,
aspects, and embodiments of the invention as well as specific
examples thereof, are intended to encompass both structural and
functional equivalents thereof. Additionally, it is intended that
such equivalents include both currently known equivalents and
equivalents developed in the future, i.e., any elements developed
that perform the same function, regardless of structure. The scope
of the present invention, therefore, is not intended to be limited
to the exemplary embodiments shown and described herein. Rather,
the scope and spirit of present invention is embodied by the
appended claims.
* * * * *